Fetching details from the dictionary...
binding (of a book)
design (of a book cover)
この本は装丁が美しい。
This book has beautiful binding design.
装丁を有名なデザイナーに頼んだ。
I asked a famous designer for the binding.
装丁で本の印象が大きく変わる。
The binding greatly changes the impression of a book.